In reply to your question, Edgar, we don't have a fuel consumption figure for the MW44 when producing 6 pounds of thrust. We have the latest figure for full thrust for the MW44 Gold - 145 ml/min (5 oz) and the figure for idle - 26ml/min (0.9 oz) but not the ones between. The figure is higher than the original MW44 (122 ml/min 4.3oz) but that is because the engine is producing more thrust. The amount of fuel used relative to thrust produced remains the same.

There is a formula which can be used for checking fuel consumption figures. The Gas Turbine Builders Association have been running an annual Engine Efficiency Competition for about 7 years, where a number of different engines are run on the same test equipment, giving an independent, accurate comparision. Over the years, the statistics show that no matter what the size of engine, it will use between 30 and 50 ml/min of fuel for each kilo of thrust produced. The lower the number, the better the engine efficiency. The best figures acheived have been in the low 30s - last year the Merlin won with a figure around 34. The previous year we acheived 35 with the MW54.

I have checked the figures given for the Flea using this formula. 6 pounds of thrust is 2.72 kilo, and 2 oz of fuel is about 60 ml. Dividing the amount of fuel by the thrust produced (60 divided by 2.72) we get 22. So it appears that the Flea is not only smaller than other engines but that the Jet Artes team have made some sort of technological breakthrough, as no engine before has come anywhere close to this figure, according to the independent tests.

We look forward to seeing this amazing feat repeated by the Flea when it is entered in the GTBA efficiency competition this year. Unfortunately, not many manufacturers submit their engines for the competition - only JetsMunt (Merlin), Wren, Behotec and Phil Heward. It is surprising that neither JetArtes nor JetCat submit engines, as according to the published thrust and fuel consumption figures on their websites their engines are acheiving an efficiency far beyond any others. On this basis they would be sure to win by a huge margin if they entered the GTBA competition. So why don't they?

Sara Parish
Wren Turbines